Do you have any Sonos devices wired at the moment? If not how far away is the router? 

You can try wiring just the left speaker. It will send audio to the right one directly.

No the rest of my speaker are wireless.  These two are the furthest away from the router (two floors up) hence the wireless issues I guess.

I have a powerline network adapter in the same room already for my PS4.  It has a spare slot in it so would be easy to set up.

Silly question but the right speaker is closer to the adapter - does it have to be the left one that it’s wired to?

In fact Sonos doesn’t officially support powerline adapters. The connection is too variable in quality. That said, many do use them without problem. See how you get on.

The main issue however is that having wired one of your Play:5s the system will flip over to SonosNet (‘wired’) mode. This means that all the other speakers will try and connect to it, so you could suffer problems with them instead.

There is a solution to all this, which is to force your system into ‘mixed mode’.

To do this you’ll have to wire both Play:5s (and yes, you can daisy-chain one off the other) then go into Settings/System/iroom name]/Products for each of the units and ‘Disable WiFi’. It’s confusing nomenclature, as you’d actually be disabling SonosNet. The Play:5s will then no longer try to ‘capture’ the other speakers, leaving them free to remain connected to the router.

You can see how everything connects in Settings/System/About My System. WM:0 means wired or SonosNet. WM:1/WM:2 means WiFi.

Follow up question:

If I wire this Play 5, will the rest of my speakers (a bunch of play 1s around the house) connect to the wireless network that the wired Play 5 has now created (if I’m reading my research correctly) or will they stay connected to my “normal” wifi?

Thanks Ratty!  Sorry your answer hadn’t appeared when I posted the above.

I’ll try wiring both of them as I’m sure I’ll have issues with the speakers at the bottom of the house if they try and use the SonosNet network.

If the Play:1s are dotted around the house there’s a possibility that they’d support one another -- SonosNet is a mesh -- and thus be able to connect back through the wired Play:5(s). However it could be a bit touch-and-go, and given that you’re resorting to powerline for the P:5s my advice above still stands.

I’m buying two cables anyway so I guess I can try one cable first, see how the play 1s react, if I’m getting drop outs then put the second cable in and turn off SonosNet to put the play 1s back on my wifi.

Even with one (or both) P:5 wired, leaving their radios enabled, there’s a chance some of the P:1s may get stuck on WiFi rather than switching to SonosNet. There could then be some instability unless/until the WiFi details were removed from the system.

One can actually view the state of the SonosNet mesh wireless connections via the Network Matrix at http://IP_address_of_a_player:1400/support/review (getting an IP from About My System). Feel free to experiment. 

However, because of the dependency on powerline, personally I’d feel more comfortable with ‘quarantining’ the P:5s by disabling their two radios.

Thanks again, cables arriving tomorrow.  I’ll let you know how I get on (although wonderfully the Play 5s have been playing all day today with no drop outs….).

If the Play:5s are ‘on the edge’ in wireless terms they could be seeing less interference at the moment.